<template>
	<view>
		<!-- <button @tap="createCanvas">签名</button> -->
		<view class="signature" v-show="showCanvas">
			<canvas class="mycanvas" canvas-id="mycanvas" @touchstart="touchstart" @touchmove="touchmove" @touchend="touchend"></canvas>
			<view class="footer">
				<view class="left" @click="finish">保存</view>
				<view class="right" @click="clear">清除</view>
				<view class="close" @click="close">关闭</view>
			</view>
		</view>
	</view>
</template>

<script>
	var x = 20;
	var y = 20;

	export default {
		data() {
			return {
				showCanvas: false,
				ctx: '', //绘图图像
				points: [], //路径点集合
				signature: ''
			}
		},
		created() {
			this.showCanvas = true;

			this.ctx = uni.createCanvasContext("mycanvas", this); //创建绘图对象

			//设置画笔样式
			this.ctx.lineWidth = 4;
			this.ctx.lineCap = "round"
			this.ctx.lineJoin = "round"
		},
		methods: {
			//关闭并清空画布
			close: function() {
				this.showCanvas = false;
				this.clear();
				let url = `/pages/index/index`
				uni.navigateTo({
					url
				})
			},
			//创建并显示画布
			createCanvas: function() {
				this.showCanvas = true;

				this.ctx = uni.createCanvasContext("mycanvas", this); //创建绘图对象

				//设置画笔样式
				this.ctx.lineWidth = 4;
				this.ctx.lineCap = "round"
				this.ctx.lineJoin = "round"
			},
			//触摸开始，获取到起点
			touchstart: function(e) {
				let startX = e.changedTouches[0].x;
				let startY = e.changedTouches[0].y;
				let startPoint = {
					X: startX,
					Y: startY
				};
				this.points.push(startPoint);
				//每次触摸开始，开启新的路径
				this.ctx.beginPath();
			},

			//触摸移动，获取到路径点
			touchmove: function(e) {
				let moveX = e.changedTouches[0].x;
				let moveY = e.changedTouches[0].y;
				let movePoint = {
					X: moveX,
					Y: moveY
				};
				this.points.push(movePoint); //存点
				let len = this.points.length;
				if (len >= 2) {
					this.draw(); //绘制路径
				}

			},

			// 触摸结束，将未绘制的点清空防止对后续路径产生干扰
			touchend: function() {
				this.points = [];
			},

			/* ***********************************************
			# 绘制笔迹
			# 1.为保证笔迹实时显示，必须在移动的同时绘制笔迹
			# 2.为保证笔迹连续，每次从路径集合中区两个点作为起点（moveTo）和终点(lineTo)
			# 3.将上一次的终点作为下一次绘制的起点（即清除第一个点）
			************************************************ */
			draw: function() {
				let point1 = this.points[0]
				let point2 = this.points[1]
				this.points.shift()
				this.ctx.moveTo(point1.X, point1.Y)
				this.ctx.lineTo(point2.X, point2.Y)
				this.ctx.stroke()
				this.ctx.draw(true)
			},

			//清空画布
			clear: function() {
				let that = this;
				uni.getSystemInfo({
					success: function(res) {
						let canvasw = res.windowWidth;
						let canvash = res.windowHeight;
						that.ctx.clearRect(0, 0, canvasw, canvash);
						that.ctx.draw(true);
					},
				})
			},
			//完成绘画并保存到本地
			finish: function() {
				let that = this;
				uni.canvasToTempFilePath({
					canvasId: 'mycanvas',
					success: function(res) {
						console.log(res)

						//上传到服务器
						uni.uploadFile({
							url: 'https://www.cdlepan.com:7443/utils/file/upload',
							filePath: res.tempFilePath,
							name: 'file',
							success: (uploadFileRes) => {
								console.log(uploadFileRes)
								if (uploadFileRes.statusCode == 200) {
									const user = uni.getStorageSync('USER_INFO');
									var data = JSON.parse(uploadFileRes.data)
									that.signature = data.data.url;
									that.$api.request('/system/user',{
										method: 'put',
										data: {'id':user.id,'signPath':that.signature}
									}).then(res=>{
										user.signPath = that.signature
										uni.setStorageSync('USER_INFO',user);
										that.clear();
										that.showCanvas = false;
										// uni.showToast({
										// 	title: '修改成功',
										// 	duration: 2000
										// });
										uni.navigateTo({
											url:`/pages/index/index`,
											success: (res) => {
												debugger
												 let page = getCurrentPages().pop(); //跳转页面成功之后
												 if (!page) return;  
												 page.onLoad(); //重新刷新页面
											}
										})
									}).catch(()=>{
									})
								}
							}
						})
						//保存到本地
						/*

						let path = res.tempFilePath;
						uni.saveImageToPhotosAlbum({
						filePath:path,
						}) */
					}
				})
			},
		}
	}
</script>

<style lang="less">
	.signature {
		position: fixed;
		top: 10px;
		left: 2%;
		z-index: 999;
		width: 96%;
	}

	page {
		background: #fff;
	}

	.container {
		padding: 20rpx 0 120rpx 0;
		box-sizing: border-box;
	}

	.title {
		height: 50upx;
		line-height: 50upx;
		font-size: 16px;
	}

	.mycanvas {
		width: 100%;
		height: calc(100vh - 200upx);
		background-color: #ECECEC;
	}

	.footer {
		font-size: 14px;
		height: 150upx;
		display: flex;
		justify-content: space-around;
		align-items: center;
	}

	.left,
	.right,
	.close {
		line-height: 100upx;
		height: 100upx;
		width: 220upx;
		text-align: center;
		font-weight: bold;
		color: white;
		border-radius: 5upx;
	}

	.left {
		background: #007AFF;
	}

	.right {
		background: orange;
	}

	.close {
		background: #A3A3A3;
	}
</style>
